[FS#1529] Feature request: preserve official firmware in spare partition

[LEDE Bugs]

A new Flyspray task has been opened.  Details are below. 

User who did this - Matthew Exon (mexon) 

Attached to Project - OpenWrt/LEDE Project
Summary - Feature request: preserve official firmware in spare partition
Task Type - Bug Report
Category - Base system
Status - Unconfirmed
Assigned To - 
Operating System - All
Severity - Low
Priority - Very Low
Reported Version - Trunk
Due in Version - Undecided
Due Date - Undecided
Details - I've been having lots of problems with my WRT1200AC router.  The 2.4GHz wifi and ethernet are not working, and no amount of reflashing or resetting seems to help.  I'd like to try reverting to the Linksys firmware, but I'm finding that's not working either (https://community.linksys.com/t5/Wireless-Routers/WRT1200AC-flashing-to-Linksys-firmware-from-OpenWRT-kernel-panic/td-p/1307907).

On the DD-WRT forum I've learned that a common "trick" is to keep the official firmware on the spare partition permanently, so that it's always possible to get back to a clean slate.  I definitely regret not doing that.  But OpenWRT automatically flashes to the opposite partition.

Could this be changed so that LuCI allows the option of choosing which partition gets written to?  It could be an "advanced" option.  Perhaps with language like:

* Flash to CURRENT partition ("linux2"), leaving existing alternate partition ("linux1") as recovery partition
* Flash to ALTERNATE partition ("linux1"), and make current OpenWRT partition ("linux2") the recovery partition

It would be extra nifty to display what's on the partitions already as well.

More information can be found at the following URL:
https://bugs.openwrt.org/index.php?do=details&task_id=1529